1. Field of the Invention
The present invention relates to a power transmission mechanism using a transmission belt, and more particularly, to a power transmission mechanism using a plurality of metal belts having different sizes and connected between a driving pulley and a driven pulley as a transmission belt.
2. Description of the Related Art
A belt transmission mechanism, one of various types of transmission mechanisms for transmitting power, transmits a rotational force of a driving pulley to a driven pulley via a belt. The belt is usually made of a rubber material which is elastic and flexible. However, the above rubber belt transmission mechanism cannot transmit huge power while changing speeds. That is, a thick belt such as a V belt is deformed when the belt runs contacting the driving pulley or the driven pulley along a curved path of its circulation due to the thickness thereof. This is because the outer circumferential surface of the belt expands while the inner circumferential surface thereof compresses. Therefore, the power transmission mechanism using the above belt is not capable of transmitting huge power.
Also, a power transmission mechanism having a structure in which metal belts are overlaid integrally has been suggested. However, the belt of the above type is limited in its elasticity so that the belt is severed or slips on the pulley, lowering the efficiency. That is, when the speed rate is not 1, since the angular velocities of the inner circumferential surface and the outer circumferential surface of the metal belt are different from one another, miscellaneous forces or slippage occurs between the pulley and the metal belt so that the belt may be damaged and the efficiency in power transmission is considerably lowered.
Further, a metal belt having a structure in which metal push blocks are stacked has been suggested. The metal belt has a structure of hundreds of stacked push blocks manufactured through a precision process one by one. However, to obtain a belt, the hundreds of precise push blocks and a metal layered belt for supporting each push block should be assembled. Thus, manufacture thereof is difficult and the cost for manufacture thereof is very high.